Cooling system foe



Patented May 26, 1931 JOSEPH SCHULMAN, OF BROOKLYN, YORK COOLING SYSTEMFOR ENGINES Application filed June 17, 1930. Serial No. 461,684.

'This invention relates to cooling systems for internal combustionengines and more particularly to such cooling systems in which thetemparatureof the water is reduced by refrigerating devices.

One object of the present invention is to do away with the use ofdevices which consume power from the engine in effecting a lowering ofits temperature, as for instance, fans draw ing cooling air in through aradiator or refrigerating systems involving compressor pumps. Inaccordance with the invention, the temperature of the circulatingcooling fluid of the engine is reduced by a self-con;

ing apparatus as compared with such a.p-'

paratus as has heretofore been suggested .for similar purposes.,Accordingly the refrigerating member or evaporator is surrounded by thefluid used for cooling the engine and in a separate compartmenttheradiator, condenser and absorber are subjected to the action of acooling fluid such as air.

These and other objects of the invention and the means-for theirattainment will be more apparent. from the following detaileddescription, taken in connection with the accompanying drawings,illustrating one embodiment by which. the invention may be realized, andin which Figure 1 is a View in side elevation showing an internalcombustion engineprovided with a cooling system in which the temperatureof the cooling liquid is reduced by a self-contained refrigerating unit,part of the casing being broken away to show the parts within; an

Figure 2 is an elevation looking in the direction of the arrows 22 ofFigure 1, partly broken away.

Referring briefly to Figure 1, the engine block 10 is illustrated asprovided with an outlet 11 for a cooling fluid, such as water, adaptedto surround the cylinders and with an inlet 12 by which the cooled waterreenters the water jacket of the engine 10. The heated water may becaused to circulate in any convenient fashion, but it is preferablycirculated by a thermo-siphon system as will be more apparent hereafter.The water flows out of the outlet 11 and into the tank 15, which mayconveniently take the place of the usual radiator and be ofsubstantially the same general dimensions. This tank 15 may be'providedwith an inlet 16 in communication with the outlet 11 of the water jacketof the engineand an outlet 17 in communication with the inlet" 12 of theengine water jacket. The means for reducing the temperature of thecooling liquid circulating through the water acket and through the tank15 are disposed within thetank 15, a more ,detailed description thereofbeing given inthe following paragraphs.

Reference will now be had to Figure 2 for an explanationof one type ofrefrigerating apparatus capable of use with this invention; the parts ofwhich are somewhat schemat-ically illustrated. A generator 20 containsthe cooling agent, .for instance, am-

monia, dissolved in a suitable absorption liquid, such as water, thesolution being indicated at 25 and the level thereof at 25a. Thegenerator is heated by the products'of combustion from the internalcombustion engine, and to this end the exhaust manifold 18 is connectedas by a pipe 21 with a heating element or chamber 22 disposed within thegenerator 20, from the. bottom of which chamber 22 the exhaust gasespass to the mufller 19 as by a pipe 23 leading out of the bottom of thechamber- 22 and passing through the bottomofthe generator 20. Althoughit will be obvious that'various substances may be used as the coolingagent, it

is preferred to use ammonia, and in describing the apparatus the termammonia will be used, but it will be understood that this is by way ofexample'only.

monia vapor is expelled, from the solu-' tion 25 in the generator 20 byheat from the chamber 22 and passes through a pipe 26 into a radiator 27positioned within a compartment 28. The arrangement of the radiator andcondenser coil in top causes the circulation of air, which functions forthe same purpose as water in the usual refrigerator. The compartment 28is preferably arranged for the passage therethrough of a cooling mediumsuch as air. In the arrangement shown, the lower port-ion of thecompartment is provided with an opening 29 for the ingress of air asindicated by the arrow A. At the upper portion of the compartment 28 anopening30 is provided for the egress of air as indicated by the arrow B.The circulation of air through the compartment 28 Will thus cool theradiator and other apparatus positioned therein to be presentlydescribed. The radiator 27 may comprise a relatively large conduitprovided with radiating fins 31 and may lie in an inclined position asshown in Figure 2. One purpose of the radiator is to condense vapor ofthe absorption liquid, which vapor is steam in the instant case, and toreturn the condensate thus produced to the generator 20. In this case,it also serves to heat the air in the upper section of chimney 28 sothat a circulation of air is established. It has been found that theintroduction of water into the evaporator seriously disturbs theefficiency of evaporation. From the very nature of the operation, thecooling agent must have a lower boiling point than the absorptionliquid. Conse quently, on decrease of temperature, the steam can becondensed without condensing the ammonia. The condensed steam flows backthrough conduit 26, which is inclined downwardly toward the generatorfor this purpose, and thus the condensate returns to the generator 20.

A condenser 32 is also positioned within the compartment 28 and may beas shown under the radiator 27 and serves, while parting with its heat,to cause a circulation of air within its chimney 28, a pipe 33 servingto carry the ammonia vapor from the upper end of the radiator to thecondenser. The

ammonia vapor is still further cooled in the condenser by the air causedto circulate thereabout and changes from the gaseous form to the liquidform.

A pipe 34 connects the lower portion of the condenser 32 to the upperportion of a refrigerating member or evaporator 35 which is positionedin the tank 15 and serves to cool the water which in turn cools theengine. The evaporator 35 is preferably provided with radiating vanes orfins 36 to facilitate the transfer of heatfrom the surrounding water tothe evaporator.

Positioned within the lower portion of the compartment 28 there isprovided an absorber 37 having radiating vanes or fins 38 similar tothose provided for the evaporator 35 for cooling purposes. The lowerportion of the evaporator 35 is connected to the lower portion of theabsorber 37 by means of a pipe, 39 whereby the ammonia vaporized in theevaporator is carried to the absorber. In

portion of the absorber 37 with the upper portion of the evaporatoradjacent to that portion of theevaporator where the pipe 34 conducts theammonia vapor thereinto.

It Will be noted that the interior of the evaporator 35 is provided withaplurality of disks 41 positioned one above'the other, each disk havingone-or more openings therein arranged so that the passage of the liquidand gaseous ammonia is through atortuous passage thereby providingalarge distributin-g surface whereby an effective evaporation isobtained.

The absorber 37 is also provided with a plurality of disks 42 similar tothe disks 41. A weak solution of aqua ammonia passes into the upperportion of the absorber 37 through a pipe 43, and after trickling downover the disks 42, during which passage it is enriched by the upwardlyflowing ammonia gas, the

resulting strong aqua ammonia solution passes out of the lower portionof the absorber through a pipe 44. The pipe 44 passes through a largerconduit or jacket 45 and is connected to an auxiliary heater 46positioned around the chamber 22. A pipe 47 is connected to theauxiliary heater 46 and discharges into the generator at a pointslightly above the level 25a of the l1qu1d therein. One end of thejacket 45 is connected' to the pipe 43 and the other endof 1 the jacketis connected by means of a pipe 48 to the lower portion of the generator20.

In operation the circulation of the water of the engine cooling systemtakes place on the thermo-siphon principle. The water heated by theengine passes upward and out through the outlet 11, and because of the.

lowered temperature in the 'tank'15, downward and back to the enginethrough the in let 12. The discharging gases from the exhaust of theengine pass through the chamber 22 and the chamber 22 thereby serves asa'heating device for the refrigerating system.

The operation of the refrigerating system for purposes of explanationmay convenient- 1y be described as involving three different circulatingsystems- The first, or main circulating system, is as follows :theammonia gas in the aqua ammonia solution in the generator 20 is drivenoff by the heat and passes generator.

into the radiator 27 where any. moisture carried over is condensed andflows back into the generator. The ammonia gas then passes into thecondenser 32 where it changes into the form of a liquid due to thecooling action of the air circulating through the compartment 28 fromthe inlet opening 29 to the outlet opening 30. The liquid ammonia thenpasses through the pipe 34 into the evaporator 35. I The ammonia gaspassing into the evaporator 35 mingles and diffuses with thehydrogenpassing into the evaporator from the pipe 40. The total pressurein the evaporator as shown on the gauge is substantially the same atthat in the condenser but due to the fact that a large portion of thegas is hydrogen, the partial vapor tension of the ammonia is muchreduced and the ammonia is vaporized at the same time absorbing heat andcooling the engine circulating water in the tank 15. The mixtureofhydrogen and gaseous ammonia then passes through the pipe 39intotheabsorber37 and up through the disks 42 where it meets the downwardstream of weak aqua ammonia supplied by the-pipe 43. A considerableportion of the ammonia is dissolved into this liquid at the same timethrowing ofi' heat which is carried away by the circulating air in thecompartment 28. The strong aqua ammonia passes out through the pipe 44into the auxiliary heater 46 and is finally discharged through.

the pipe 47 into the generator 20.

A- secondary circulating system is that of the aqua ammonia between thegenerator 20 and the absorber.37.' The weak aqua am monia from thegenerator 20 passes out from the generator at the lower portion thereofthrough the pipe 48, through the Jacket 45 and upward through the pipe43, discharging into the upper" portion of the absorber 37. The strongaqua ammonia from the absorber passes out therefrom through the pipe 44,through the auxiliaryheater 46, upward through the pipe 47 and into theIt will be noted that the level of theliquid in the generator 20 ishigher than that in the absorber 37. The pumping action which isnecessary to raise the liquid from the lower level existing in theabsorber 37 to that in the generator 20 is produced by the auxiliaryheater 46.. The heater vaporizes a sufiicient amount of the ammonia sothat the pipe 47 .is partially filled with liquid and partially filled.with gas.

less than the total height of the liquid in the pipe 44 so that theliquid in pipe 44 is able to force the lesser head of liquid in the pipe47 up into the generator. It will be noted that the jacket 45 acts as acounterfiow heat interchanger, the hot weak aqua ammonia from theP beingcooled some:

what before 'it is discharged into the ab- The. total height of theliquid in the pipe 47 is sorber through the pipe 43 while at. the sametime the .cool strong aqua ammonia from the pipe 44 is heated somewhatbefore it onters the auxiliary heater 46.

The third circulating system is that which takes place between theevaporator 35 and the absorber 37. The liquid ammonia entering Thisprocess of diffusion of the cooling.

agent or ammonia into the auxiliary agent (which obviously entailsdifluslon of the auxiliary agent into the cooling agent) results in Ievaporation of the cooling agent whereby heat is abstracted from theengine cooling fluidsurrounding the evaporator without howevernecessitating change in actual or total pressure between the c ondenserand the evaporator.

Any auxiliary agent may be contained within the evaporator to work withthe ammonia as a cooling agent so long as these substances have verygreatly different specific molecular weights a result of which it ispossible to obtain an eflicient circulation and effect difiusion.

As will be readily understood, the ammonia gas and hydrogen mixed in theevaporator 35 flow downwardly therein and through pipe 39 into the lowerpart of the absorber 37.

In the absorber, the gas mixture comes into contact with weak absorptionliquid supplied.

thereto from the generator 20 through pipe 43 and distributor disks 42,i. e., with liquid in which there is relatively less cooling agentdissolved. With this. grouping of the gaseous mixture and the absorptionliquid, which, in. the illustration given, is water, the result is anabsorption or dissolving of ammonia by water and a liberation ofhydrogen. Now, since, we above stated, hydrogen is of markedly difierentspecific weight than ammonia, and since hydrogen is very much lighterthan ammonia, it will be seen that the weight per unit volume of gasafter being freed from ammonia 1n the absorber is less;

than the weight of gaseous mixture perunit volume formed in theevaporator. Therefore, with a suitable interconnection of the evaporatorand absorber, there will be preponderance of downwardly directedgravitational force produced, in the evaporator for causing automaticcirculation of gas between and through the evaporator 35 and absorber37. The hydrogen passes upwardly in the absorber 37 and through the pipe40. into the upperpart of the evaporator 35. .where it is again mixedwith the heavier ammonia vapor and is carried downwardly as part of themixture through the pipe 39 to the lower part of the absorber in whichthe ammonia is forced into the solution and the light hydrogen is freedand again passes upwardly Within the absorber. There is thus establishedan automatic circulation of gas between and through the evaporator andabsorber which makes it possible to obtain refrigerating apparatuswithout moving parts.

Various modifications will occur to those skilled in the art in thecharacter of refrigeration apparatus combined with the engine coolingsystem as well as in the configuration and construction of the componentelements thereof so long as waste heat of the engine is utilized toeffect circulation of the refrigerant and no limitation is intended bythe phraseology of the foregoing description or illustrations in theaccompanying rawings except as indicated in the appended claims.

This application is a continuation in part of United States application,Serial No..327,- 329 filed December 20, 1928, and abandoned June 17th,1930, for cooling system for engines.

What is claimed is 1. A cooling system for an internal combus tionengine comprising an engine cooling fluid circulating system, arefrigerating system for cooling said fluid of a type adapted to beoperated by energy supplied thereto in the form of heat, and means forsupplying heat thereto from the waste heat of the engine.

2. A cooling system for an internal combustion engine comprising anengine cooling fluid circulating system, a refrigerating system forcooling said fluid of a type adapted to receive the energy necessary forits operation solely in the form of heat, and means for supplying heatthereto from the waste heat of the engine.

3. In a cooling system for an internal combustion en ine, incombination, a container for the engine cooling fluid, refrigeratingapparatus disposed therein, and containing a cooling agent and means tovaporize said cooling agent by the waste heat of the engine.

4. In a cooling system for an internal combustion engine, incombination, a container for the engine cooling fluid, refrigeratingapparatus disposed therein and containing a cooling agent, a generatorfor the cooling agent and means to conduct exhaust gases of the engineto the generator.

5. A cooling system foran internalcombustion engine having an exhaustmanifold comprising an engine cooling fluid circulating system, anabsorption type of'refrigerating system for cooling'said fluid, andmeans for supplying heat energy to said refrigerating system from theexhaust manifold of the engine.

6. 'A cooling system for an internal combustion engine having an exhaustmanifold comprising an engine cooling fluid circulating system, anabsorption type of refrigerating system for cooling said fluid, meansfor supplying heat energy to said refrigerating system from the exhaustmanifold of the engine, and means within-the refrigerating system forproducing circulation o the cooling agent with the system hermeticallysealed to the outside air.

7. In a cooling system for an internal combustion engine, incombination, a container, means to conduct heated cooling fluid from theengine to the top of the container, means to conduct the cooling fluidfrom the bottom of the container to the engine, refrigerating apparatuscomprising an evaporator in the container and surrounded by the coolingfluid of the engine, a condenser through which a cooling agent passes tothe evaporator, an absorber to which the cooling agent passes from theevaporator, a generator for the cooling agent connected with thecondenser and the absorber, a heating chamber within the generator, andmeans to conduct exhaust gases from the engine to said chamber.

8. In a cooling system for an internal combustion engine, incombination, a container, means to conduct heated cooling fluid from theengine to the top of the container, means to conduct the cooling fluidfrom the bottom of the container tothe engine, refrigerating apparatuscomprising an evaporator in the container, a radiator, a condenser andan absorber in a separate compartment, a generator for the cooling agentoutside of the container and the compartment but connected with thecondenser and the absorber, means for connecting the condenser and theabsorber to the evaporator, a heating chamber within the generator, andmeans to conduct exhaust gases from the engine to said chamber.

9. In a cooling system for an internal combustion engine, incombination, a container, means to conduct heated cooling fluid from theengine tothe top of the container, means to conduct the cooling fluidfrom the bottom of the container to the engine, refrigerating apparatuscomprising an evaporator in'the container, a radiator, a condenser andan absorber in a sep aratecompartment, a generator for the cooling agentoutside of the container and the compartment but connected with thecondenser and the absorber, means for connecting the condenser and theabsorber to the evaporator, a heating chamber. within the generator, andmeans toconduct exhaust gases from the engine to said chamber, aseparate compartment having an opening on top and an opening in thebottom, the radiator and condenser being so placed as to create a draftto thereby cool the radiator, condenser and absorber.

In testimony whereof I affix my signature.

JOSEPH SCHUL'MAN.

